Advantages of multi-stream/multi-spatial video switching architectures are well understood. High scalability, high quality, and low latency are included among the advantages of Scalable Video Coding (SVC) and video simulcast implementations. Disadvantages of these methods, however, include higher bandwidth usage as the number of participants increase, and any single stream devices are limited to one participant.
Traditional video conferencing solutions create a composite consisting of multiple video windows resized and arranged in a configurable layout. The result is a single video image containing all participants, delivered from the conferencing mixer to each participant over a single stream. The advantages of this method include bandwidth efficiency and less dependence on client capabilities. But disadvantages include scalability issues, high latency, less efficient use of resources, and less flexibility in window placement on the endpoints.